New alpha-(N)-heterocyclichydrazones: evaluation of anticancer, anti-HIV and antimicrobial activity.

A series of 3- and 5-methylthiophene-2-carboxaldehyde alpha-(N)-heterocyclichydrazones were synthesized and submitted to an in vitro investigation of their anticancer, anti-HIV and antimicrobial activities. Some of the newly synthesized compounds were found to possess antiproliferative properties, whereas no anti-HIV activity was seen; the most active of the series was the derivative 2i, which exhibited tumour growth inhibition activity against all cell lines displaying GI50 values between 1.63 and 26.

High affinity central benzodiazepine receptor ligands. Part 3: insights into the pharmacophore and pattern recognition study of intrinsic activities of pyrazolo[4,3-c]quinolin-3-ones.

Novel 2-phenyl-2,5-dihydropyrazolo[4,3-c]quinolin-3-(3H)-ones (PQs) endowed with high affinity for central benzodiazepine receptor (BzR) were synthesized. In particular, 9-fluoro-2-(2-fluorophenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one (2(2)) showed binding affinity in the subnanomolar concentration range and proved to be in vitro a potent antagonist. This finding allowed the nature of the hydrogen bonding receptor site H(2) to be established, as located between the N-1 nitrogen of the PQ nucleus and the ortho position of the N-2-aryl group.

Specific targeting of acetylcholinesterase and butyrylcholinesterase recognition sites. Rational design of novel, selective, and highly potent cholinesterase inhibitors.

Tacrine-based AChE and BuChE inhibitors were designed by investigating the topology of the active site gorge of the two enzymes. The homobivalent ligands characterized by a nitrogen-bridged atom at the tether level could be considered among the most potent and selective cholinesterase inhibitors described to date. The nitrogen-containing homobivalent ligands 3e,g and the sulfur-containing 3h validated the hypothesis of extra sites of interaction in the AChE and BuChE active site gorges.

Synthesis and anti-tubercular evaluation of 4-quinolylhydrazones.

A series of 4-quinolylhydrazones were synthesized and tested against Mycobacterium tuberculosis H37Rv. Preparation of the title compounds was achieved by reaction of 4-quinolylhydrazine and aryl- or heteroaryl-carboxaldehyde. For the most of derivatives interesting antitubercular properties were showed; two compounds (3(2) and 3(25)), identified as the most active, were tested also against Mycobacterium avium.

Synthesis and pharmacological activity of 1,2,4-triazolo[4,3-a]quinolines.

The synthesis of a series of 1,2,4-triazolo[4,3-a]quinoline derivatives is described; their structures were assigned by 1H NMR and analytical data. The new compounds were tested in vivo for their antiinflammatory and analgesic activities, as well as for their ulcerogenic action. Some of the tested triazoles showed an analgesic activity in the acetic acid writhing test and antiinflammatory properties on carrageenan paw edema assay.